A woman sent an anonymous audio recording to Andrew Hanlon's sister, Melanie, and brother-in-law Nathan Heise at their home in Oregon on Friday claiming she witnessed the fatal shooting in the town of Silverton.

On the disc, she claimed that the 20-year-old was running barefoot, had stumbled, and was attempting to get up when he was shot up to seven times by the police officer.

"We're not passing it on to a lawyer -- we're thinking now that maybe we need to pass it on to the DA," Mr Heise said yesterday. "It might not be evidence, but then again it might be. We're not sure so we're going to give it to the DA."

It had been reported that the family was going to pass the recording on to a lawyer with a view to joining hundreds of other families across America taking action against police forces whose officers have shot dead mentally-ill relatives.

Melanie Heise has said her brother had slight psychological problems but appeared fine before the shooting.

Mr Heise said the family would be meeting with the investigating district attorney for the first time tomorrow, but admitted they were not confident of new information emerging from the authorities.

"We're still being met with silence and that's likely to be the case while the investigation is ongoing unfortunately," he said.

"But it will be good to put a face to the man who is investigating. There's been no lull in the media interest. We had to stay with friends last night because it's been impossible to get any sleep here."

He declined to comment further on the audio recording.

On the disc, the witness said she was related to the woman who had called the police after Mr Hanlon, apparently in a confused and delusional state, had banged on her door at around 11pm last Monday.

The woman says her relative had called the police believing her home was being broken into, before calling her husband who drove to the house with a friend.

The pair chased Mr Hanlon, before a policeman arrived on the scene and saw Mr Hanlon running down the street in his bare feet. She claimed that the young man, originally from Dundrum in Dublin, tripped and was trying to get up when the officer opened fire.

The policeman, Tony Gonzalez, is on paid leave pending the outcome of an investigation into the shooting.

Mr Hanlon's family believes he had been on his way to his sister's home when he got lost and was knocking on doors to ask for directions. His family have said he had been suffering with paranoia and delusions in recent times but had never been diagnosed.

Mr Heise said yesterday that Mr Hanlon's mother, Dorothea, was expected in Oregon in the next few days.